Decorated wall covering



'atented May 25, 1948 Albert E. Gelsler, Scandale, Clillord "1. Rollo,cia J. 'luttleylilew York, N. Y., assignors to lnterchemicalCorporation,

New York, N. Y.,- a corporation of Ohio No Drawing. Application mi. 11,1942,

serum. 434.212

Claims. (01. 154-550)" Yonkers, and Fran coverings, and which can behung like ordinary wallpaper, but which 1 is characterized by excellentwaterproofness and unusual resistance to wear.

Wallpaper provides a highly desirable cheap decoration for homeinteriors, but is subject to premature deterioration because the paper,when soiled, cannot be cleaned easil and economically. The use ofwash-resistant prints has been widely adopted in an attempt to overcomethis objection, but even the best of the so-called washable" wallpapersare not entirely satisfactory, particularly where exposed to water (asin bathrooms and kitchens) and to children's dirty hands. The market forreally washable products has been filled by oilcloth, linoleum andcoated fabrics, and more recently by decorated foils laminated tofabric. These products are all very expensive, and most of them arerather diflicult to hang.

Attempts to protect the decorations on ordinary wallpaper, and thusobtain washfastness, by lacquer coatings or by the lamination oftransparent or decorated foils thereto, have been made, in an effort toproduce a cheap and really washable wall covering. But these attemptshave failed, due to the fact that the coated or laminated wallpapers donot hang readily, and stick to the walls poorly. Apparently, thisfailure is due to the fact that the outer surface of the coated paper issubstantially impervious to moisture, whereas the ordinary wallpaperpermits rapid passage of moisture therethrough; since aqueous pastes areused in hanging the paper, trouble ensues, because of the water trappedback of the paper.

We have discovered that wallpapers, impervious on one side thereof, maybe manufactured and successfully applied to walls, by using a base papercomprising a sized calendered sheet, which wets through with water veryrapidly, and have I developed a test whereby such papers can bedistinguished from other papers.

In our test, three-inch diameter circles of paper are placed on thesurface of a body of water, and the curling of the paper observed. Allpapers will curl to a maximum, and then flatten out. We have found that,by observing the time of maximum curl, papers which can be imperviouslycoated on one side and still hung can be readily chosen. If the averagetime of maximum curl, using several samples, is below ten seconds, goodresults can be obtained; if the time is between about ten and fifteenseconds, just passable results are obtained; while times of sixteenseconds and over (such as are obtained with ordinary wallpaper stocks)produce unsatisfactory sheets.

Typical of the papers which can be used are light weight papers (up toperhaps 50 or 60 pounds per. ream). which are lightly sized an calm--dered, but uncoated, for example, some kraft stocks, and light weightHibulk" (a printing stock sold by West Virginia Pulp and Paper Companymade by the soda process from about 70% of short deciduous fibers and30% of long coniferous fibers, sized with rosin, having a density of 5to seconds, and having a low Mullen). Thus, all-pound kraft shows a timeof maximum curl of 7 seconds, till-pound Hibulk a time of maximum curlof 6 seconds.

Coated stocks, unsized highly absorbent stocks such as newsprint,heavy-weight sized stocks (such as IO-pound kraft or I-Iibulk"), heavilysized papers such as most writing papers, and all the wallpaper stock wehave tested, have proven unsatisfactory. Thus; 'lq-pound kraft has amaximum curl time of thirty seconds; conventional wallpapers are worse,with a time of to seconds.

The paper may be printed in conventional fashion, and coated with awater-resistant lacquer, appliedas liquid or molten coating, but weprefer to laminate a thin sheet of water-resistant foil (e. g.,cellulose acetate, cellulose aceto-butyrate, ethyl cellulose, vinylresins, Pliofilm) to the paper. Such a coating should not be too thick,or hanging properties will be disturbed: foil of up to about 3 mils may,however, be used safely. Most preferably, the top face of the foil ismatte, and the decoration is printed or otherwise applied to the foil onthe side to be laminated. This takes advantage of the fact that the foilis ordinarily a better printing surface than the paper, and particularlythat there is no danger of obscuring the print by the use of an adheisvewhich would have to be interposed between the foil and the print.

As typical of our invention, we printed a design on the glossy side of a3-mil cellulose acetate foil with a nitrocellulose lacquer inkcontaining about 10% of methyl ethyl ketone, leaving the matte side tobe used as the top surface. This solvent attacks the acetate, causingpermanent adherence of the ink, which would not be attained in theabsence of a solvent for the acetate. A printed foil in which the inkwas merged into the foil was thus obtained. The ink was thenover-printed, from an over-all intaglio plate, with a. coating whichacts both as a. colored background for the print, and as an adhesive,comprising Parts by weight /2" RS nitrocellulose 10 Alkyd resin (35%oil-modified) l7 in Toluol 17 Plasticizer 5 Titanium dioxide 12 Solvent39 While this coating'was still wet, the foil was laminated to acalendered, sized paper sheet having a 3-second maximum curl time, andweighing thirty pounds per ream. The resultant decorated paper hungwell, was washable and resistant to dirt. As distinguished from evenmost wallpapers, this wall covering showed no curling of the edges whenonce applied to the wall, largely eliminating the touch-up worknecessary in most wall covering Jobs. The wall covering itself could besmeared with ink, crayon, butter, etc., and cleaned without a trace withsoap and water or gasolinea property not possessed by other wallcoverings.

Examples of coatings and foil laminations, of varying adhesives, and ofpapers, could be multiplied indefinitely. Various water-resistant foilscan be used, such as nitrocellulose, cellulose acetate, cellulose mixedesters, cellulose ethers, and various resins (polyvinyl esters, andhalides), Pliofilm, etc. Cellulose hydrate (Cellophane) and thehydrophilic cellulose derivatives (e. g., methyl cellulose) and resins(e. g., polyvinyl alcohol) are unsatisfactory. The basic thought of thisinvention, however, is in the choice of certain papers which permithanging even when one side is protected with a water-impervious film,and is expressed in the claims.

We claim:

1. A wall covering consisting of paper having one side thereof coveredwith a water-impervious film tightly adherent to the paper, the paperbeing characterized by having a time of maximum curl, when a three-inchcircle thereof is placed on the surface of a body of water, of fifteenseconds or less.

2. A wall covering consisting of paper having one side thereof coveredwith a water-impervious film tightly adherent to the paper, the paperbeing characterized by having a time of maximum curl, when a three-inchcircle thereof is placed on the surface of a body of water, of below tenseconds.

3. A wall covering consisting of paper having one side thereof coveredwith a water-impervious film tightly adherent to the paper, the paperbeing characterized by being uncoated but sized and calendered, andhaving a time of maximum 4 curl, when a three-inch circle thereof isplaced on the surface of a body of water, of below ten seconds.

4. A wall covering consisting of paper having one side thereof laminatedto a water-resistant foil carrying a design on the side thereoflamihated to the paper, and tightly adherent to the paper, the paperbeing characterized by having a time of maximum curl, when a three-inchcircle thereof is placed on the surface of a body of water, of fifteenseconds or less.

5. A wall covering consisting of paper having one side thereof laminatedto a water-resistant foil carrying a design on the side thereoflaminated to the paper, and tightly adherent to the paper, the paperbeing characterized by having a time of maximum curl, when a three-inchcircle thereof is placed on the surface of a 'body of water, of belowten seconds.

6. A wall covering consisting of paper having one side thereof laminatedto a water-resistant foil carrying a printed design on the side there oflaminated to the paper, and tightly adherent to the paper, the paperbeing characterized by being uncoated but sized and calendered, andhaving a time of maximum curl, when a threeinch circle thereof is placedon the surface of a body of water, of below ten seconds.

: ALBERT E. GESSLER. CLIFFORD J. ROLLE. FRANCIS J. TU'I'I'LE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,848,686 Arnold Mar, 8, 19321,990,098 Seymour Feb. 5, 1935 1,992,249 Snyder Feb. 26, 1935 2,129,929Gurwick Sept. 13, 1938 OTHER REFERENCES '1', A. P. P. I. TentativeStandard-Water Resistance of Paper, T433, m-35, 3 pp. (1935). (Copy inDiv. 56.)

